Which nerve provides sensory innervation to the buccal gingiva in the maxillary molar region and adjacent facial mucosal surfaces?

• A. External branch of PSA
• B. MSA
• C. ASA
• D. Infraorbital nerve

Answer: (A)

The buccal gingiva of the maxillary molar region and the adjacent facial mucosa are supplied by the external (buccal) branch of the posterior superior alveolar nerve. This branch travels along the buccal aspect to innervate the soft tissue surrounding the molars, which is why it’s the nerve responsible for sensation in that specific gingival and mucosal area. In contrast, the anterior superior alveolar nerve serves the maxillary anterior teeth and their gingiva, the middle superior alveolar nerve serves the premolars (and often the MB cusp of the first molar) and their gingiva, and the infraorbital nerve mainly handles sensation to the midface and upper lip/cheek region.